Educational model of pharmaceutical device



July 9, 1968 J. c. MICHALEK ET AL 3,391,477

EDUCATIONAL MODEL OF PHARMACEUTICAL DEVICE Filed Oct. 22, 1965 Inventors John. C.Mic|1ale K Maurice R. Naaareth. 33/ Robert L. Niblack 3,391,477 EDUCATIONAL MODEL OF PHARMACEUTICAL DEVICE John C. Michalek, Lake Villa, and Maurice R. Nazareth, Waukegan, Ill., assignors to Abbott Laboratories, North Chicago, 111., a corporation of Illinois Filed Get. 22, 1965, Ser. No. 501,627 5 Claims. (Cl. 35-49) This invention relates in general to educational models for illustrating pharmaceutical devices and more particularly to an educational model of a sustained release dosage form medicament composition used for oral administration of drugs.

In the past, many medicaments were incorporated in the pill or capsule form. In these forms the drug was present in concentrated form, and upon ingestion into the host the drug was either rapidly dissolved, releasing the total dosage within a short time, or it passed through the digestive tract more quickly than the time required to dissolve the medicament thereby rendering the drug ineffective. These difiiculties prevented the use of many drugs in oral dosage form. Within recent years, the importance of sustained release dosage forms has been recognized and drug compositions have been developed whereby drugs may be administered by the oral route while insuring that the drug will be released slowly into the hosts system over a period of several hours. Such a device, as described in US. Patent 2,987,445, is comprised of a non-toxic synthetic plastic matrix in which is uniformly distributed a drug and, if desired, a water-soluble excipient. After ingestion into the host, the moisture of the digestive tract leaches the drug out of the plastic carrier over a period of several hours, after which the plastic carrier passes through a digestive tract and is excreted substantially unchanged except for the loss of the drug originally contained therein.

In connection with the development of these sustained dosage drug compositions, it has become quite important that physicians and others dealing with drugs and medicaments be apprised of such drug compositions and how they work in order that these particular forms of medicaments gain acceptance in the field and be of commercial success. The problem which has been encountered in familiarizing these groups with such new devices is the lack of time, especially among physicians, necessary to illustrate these devices. It has been estimated that a hospital supply salesman has approximately three minutes of time per doctor to display new devices and accept orders for needed supplies. It becomes obvious that many new devices and drug compositions requiring more than a matter of minutes to illustrate or explain do not readily come to the attention of physicians and other professional people in the drug industry due to this lack of sufficient time.

The aforementioned problem is particularly acute Where the new device is one developed for the oral administration of drugs since the device is, of necessity, quite small and takes more than a matter of minutes to demonstrate. Such has been the problem of demonstrating the sustained release drug composition which has an effective period of some eight hours or more before the drug contained within the carrier is leached out.

It is the object of this invention, therefore, to provide an educational device which can easily and quickly demonstrate what the sustained release dosage form medicament composition is and how it operates.

Another object of the present invention is to provide a large scale model of sustained release drug composition which can be displayed simultaneously to a group of persons which will accurately illustrate the method by which this composition operates all within a period of a few minutes.

atent "ice Other objects and advantages of the present invention will be more readily appreciated by reference to the following description when considered in connection with the accompanying drawings.

FIGURE 1 is a perspective view of the device in assembled relation;

FIGURE 2 is a top plan view of the upper surface of the top member;

FIGURE 3 is a side elevational view of the device;

FIGURE 4 is a top plan view of the bottom member engageable with the member as shown in FIGURE 2;

FIGURE 5 is an exploded fragmentary transverse sectional view illustrating the engaging means of the two members as shown in FIGURES 2 and 4; and

FIGURE 6 is a fragmentary sectional view taken along the line 66 as shown in FIGURE 3.

Like references are used to designate components having like construction, function and relative position, and the device as a Whole is designated as D.

In general, the device contemplated by this invention consists of one or more at least partially transparent members which are engageable in tight-fitting relationship. A surface of one member contains a network of interconnecting canals having terminal endings along the periphery of the device, and said canals having, in turn, an indicator material packed throughout. When the members are in engaged position, the canals containing the indicator material are completely encased such that the material is exposed to the outer environment only at the terminal endings of the canals along the periphery of the device. The indicator material possesses some physical or chemical property, such as solubility or color-changing ability, which can be activated upon contact with a suitable sol vent or liquid. When the device is immersed in an appropriate liquid, the liquid contacts the material and thereby activates the indicator property. For example, a solvent may start dissolving the packed material starting at the terminal ends of the canals and working in toward the center of the device, or the solvent may cause a change of color in the material as it is gradually drawn into and through the device by capillary action. The device, being of sufiiciently large dimensions and at least partially transparent, simulates the action of a sustained release dosage form of medicament, thereby illustrating to any observer the operation of such devices. In the case of water soluble indicators this may be enhanced by incorporating ingredients which produce gas and eifervesce.

Although the device as shown herein is described in terms of having two engageable members, it is just as easily possible to have a device according to the objects of this invention composed of a single member or having more than two members. The number of members used in formulating this device is merely a matter of engineering and practicality. It has been found that a two-membered device admits of simplicity in design and ease of manufacture while still effecting the objects of this invention. Thus, although the preferred embodiment as described herein consists of two members, a device composed of various numbers of members can be utilized within the scope of this invention.

It is clear that the shape of the respective members or of the device as a whole is immaterial. It may be moulded in the form of a triangle, cylinder, octahedron, circle, or any other geometric shape. In the preferred embodiment of this invention as described herein, the members of said device are in a circular configuration. This shape proves to be an easy and economical fonm to manufacture, while at the same time closely simulating the actual shape of many oral dosage medicaments.

Where the device is formulated from two or more members, then such members must be engageable by some engaging means. The objects of this device are accomplished if the members are engaged in tight-fitting relationship such that the network of interconnecting canals and the material contained therein are complete- 1y encased and shielded from the outer environment. The engaging means may consist of one or more cylindrical protrusions extending vertically from the surface of one member which friction-fit into cylindrical bores of approximately the same diameter in the other member(s). Alternatively, the members may be engaged by some adhesive material, or by interlocking notches, or by other means which effectuate a tight-fitting relationship.

The network of interconnecting canals are tooled into the surfaces of one or more of said members in such a fashion that when the members are in engaged position, the canals are completely encased and shielded from the outer environment at all points except the terminal ends of said canals along the periphery of the device. The canals are packed with a material which can visibly display the action of a solvent or liquid as it contacts the material at the terminal ends of the canals and gradually transverses the canals. The material may consist of a colored soluble material such that an observer can view the material being dissolved as the solvent permeates through the device, or alternatively, the material can merely be color-changeable upon contact with a suitable liquid as it permeates and transverses the device. In effect, any material which can visually exhibit the gradual action of the solvent or liquid as it is drawn through and permeates the device by acting upon some physical or chemical property of the material may be employed to effectuate the desired objects of the invention.

Referring now to the drawings, in FIGURE 1 the bottom member of the device D is shown in engaged position with the top member 11 of the device, held together by the engaging means 12. The canals 13 of the bottom member are schematically shown dispersed throughout, said canals terminating along the annular edge 14 of the device.

In FIGURE 2 of the top member 15 composed of transparent plastic material is illustrated with the engaging means 16 located in the center of said member. Gas outlet vents 17 are shown diametrically opposed to each other, positioned tangential to the engaging means 16. These vents are open to the outer environment thereby facilitating dissolution, as will be more precisely described hereafter.

FIGURE 3 shows the top member 11 engaged with the bottom member 10 such that the outer terminal ends of the canals are exposed along the periphery 14 of the device.

FIGURE 4 is a top view of the bottom member 10 showing the interconnecting canals 18 distributed throughout said member with the engaging means 19 located in the center of the member.

FIGURE 5 shows in detail the engaging means of the top and bottom members. The top member 11 is provided with a cylindrical protrusion 20 extending vertically from the lower surface 21 of said member and located in the center of same. Tubular gas outlet vents 22 and 23 are positioned diametrically opposed to each other, transversing said top member, tangential with the engaging means of said member, having apertures 24 and 25 along the upper surface 21A of the top member and terminating in an annular aperture 26 at the lower surface 21 of said memher.

The bottom member 10 is provided with an engaging means consisting of a truncated cone portion 27 in the upper part of said member in conjunction with a cylindrical core portion 28 of approximately the same diameter as the cylindrical protrusion 20 of the top member. Said engaging means transverses the bottom member in the center of same. Engagement is effected by inserting the cylindrical protrusion 20 into said cylindrical core 28 where a tight friction-fit results.

Interconnecting canals 29 are shown in cross-sectional view. The inner terminals of said canals are continuous with the truncated cone portion of the engaging means of the bottom member, as illustrated at 30.

FIGURE 6 shows the members in engaged position with the engaging means 20 of the top member 11 friction-titted against the walls 31 and 32 of the engaging means of the bottom member. The annular aperture 26 is shown in conjunction with the truncated cone 33 of the bottom member 10, thereby forming an annular cavity open to the outer environment through the gas outlet vents 22 and 23 by way of outlet apertures 24 and 25.

In the preferred embodiment as illustrated in the accompanying drawings, the device is composed of two members, a top member and a bottom member, both of which are made of a clear, transparent plastic matrix. Both members are circular in shape having flat surfaces on each side. The top member has its engaging means centrally positioned, said means comprising a cylindrical protrusion extending vertically from the under surface of said member to a length approximately equal to the thickness of the bottom member. The cylindrical protrusion is surrounded by an annular aperture disposed within the under surface of said member. A pair of tubular gas outlet vents are positioned adjacent to the cylindrical protrusion diametrically opposed to each other, transversing said top member, and opening into the annular aperture.

The bottom member has its engaging means also centrally positioned, said means comprising a truncated cone portion in the upper half of the members having a diameter at its widest point equal to the diameter of the annular aperture of the top member, in continuation with a cylindrical core portion in the lower half of said member, said core portion having approximately the same diameter as the cylindrical protrusion of the top memher. The upper surface of said member has a network of interconnecting canals disposed therein having outer terminal endings along the periphery of the device and inner terminal endings along the truncated cone portion of the engaging means of said member. The canals are packed with a soluble material preferably containing chromogenic additives such that there i a sharp contrast of color between the packed material and the matrix thereby facilitating visual observation of the device in operation.

The two members are engaged by inserting the cylindrical protrusion of the top member into the receiving core of the bottom member such that the under surface of the top member and the upper surface of the bottom member come into contact with each other. By having the diameter of the protrusion approximately equal to or slightly larger than the diameter of the core portion of the bottom member, a tight friction-fit results when the protrusion is pressed firmly into the core. Furthermore, the annular aperture of the top member is thereby positioned directly above and on top of the truncated cone portion of the bottom member, these apertures having the same diameter, resulting in an annular cavity surrounding a portion of the protrusion around which the canals have their inner terminal endings. The gas outlet vents transverse the top member and open into this annular cavity. In the engaged position, the interconnecting canals are enclosed by the top member, being exposed to the outer environment only at the outer terminal endings along the periphery of the device and at the inner terminal endings through the gas outlet vents.

When the device is immersed in a suitable solvent, the solvent makes contact with the soluble material in the canals at the outer terminal endings, initiating the dissolution of said material. As dissolution commences, the air within the device, and any gases formed during dissolution, escapes through the gas outlet vents. The outlet vents thereby prevent any back-up of gas which would essentially inhibit the leaching out of the soluble material. The leaching commences at the outer terminal endings and the leaching action progresses inwardly until all of the material is leached or washed out of the plastic device. The material is dissolved or leached out of the device preferably within 1 to minutes after immersion in solvent, thus rapidly illustrating in understandable fashion the mechanics of a sustained release dosage form of medicament in human hosts.

While in the foregoing specification various preferred embodiments have been described and shown, no unnecessary limitation should be understood therefrom as it will be appreciated by those skilled in the art that this invention is susceptible to many variations without departing from the spirit and scope thereof.

We claim:

1. A device for illustrating the leaching action of a liquid as it moves into and through said device from an outer environment comprising a substantially transparent top member having a flat upper and lower surface and a predetermined periphery; a substantially transparent bottom member engageable with an engaging said top member, having a fiat upper and lower surface and a periphery equal to that of said top member, said top and bottom members each having a predetermined thickness; disengageable engaging means positioned on the lower surface of the top member and on the upper surface of the bottom member arranged in juxtaposition with the engaging means on said top member whereby said members may be abutted in separable relationship; the bottom member having interconnecting canals disposed within its upper surface with terminal endings along the periphery of said member such that the canals are completely enclosed when the top and bottom members are in an engaged position, exposed to the outer environment only at said terminal endings; and an amount of indicator material disposed within said canals which upon contact with a suitable liquid is leached out from the canal into the liquid in the outer environment as the liquid flows through the canals.

2. A device as described in claim 1 wherein the engaging means comprises in the top member a depending cylindrical protrusion centrally positioned on the lower surface of said member and extending vertically from said surface a length equal to the thickness of the bottom member, the bottom member having a centrally positioned truncated cone portion in the upper half of the member and a cylindrical core portion in the lower half of said member, said core portion having a diameter of approximately the same size as the diameter of the cylindrical protrusion of the top member such that the cylindrical protrusion is engageable with the cylindrical core portion of the bottom member to thereby effect a friction-fit and join the two members together.

3. A device as described in claim 1 wherein the top and bottom members are transparent water-insoluble plastic.

4. A device as described in claim 1 wherein the indicator material disposed within the interconnecting canals contains color-contrasting chromogenic agents.

5. A device for illustrating the leaching action of a solvent as it moves into and through said device from an outer environment comprising a disk-shaped transparent plastic top member having a lower and upper surface and a predetermined periphery, diameter, and thickness; a disk-shaped transparent plastic bottom member having a lower and upper surface and a periphery, diameter, and thickness equal to that of said top member; a depending cylindrical protrusion of a predetermined diameter centrally positioned on the lower surface of the top member and extending vertically from said surface a length equal to the thickness of the bottom member, the lower surface of the top member having an annular aperture of a predetermined diameter circumscribing said cylindrical protrusion, said top member having two transverse tubular gas outlet vents arranged diametrically opposed to each other and tangential with the cylindrical protrusion, opening into the annular aperture, the bottom member having a truncated cone portion centrally positioned in the upper half of said member having a diameter at its widest point equal to the diameter of the annular aperture, and a cylindrical core portion in the lower half of said member having a diameter approximately equal to that of the cylindrical protrusion such that the protrusion friction-fits into said core portion of the bottom member bringing the lower surface of the top member in contact with the upper surface, the bottom member having a network of interconnecting canals disposed within its upper surface with outer terminal endings spaced around the periphery of the member and inner terminal endings spaced around the truncated cone portion of said member such that said canals are completely enclosed when the top and bottom members are engaged, exposed to the outer environment only at the outer terminal endings and at the inner terminal endings through the gas outlet vents, and said canals having an amount of soluble material including chromogenic additives disposed within same which upon contact with a suitable solvent is leached out of canals into the solvent in the outer environment surrounding the device all in from about one to about fifteen minutes, whereby the action of a sustained release dosage form of medicament is simulated and illustrated.

References Cited UNITED STATES PATENTS 2,987,445 6/1961 Levesgue 167-82 3,044,938 7/1962 Halley 167-82 3,317,394 5/1967 Fryklof et al. 167-82 OTHER REFERENCES Laboratory Control of Durretter, a Sustained Release Tablet, John Sjogren, October 1960, pp. 198-200.

EUGENE R. CAPOZIO, Primary Examiner.

W. GRIEB, Assistant Examiner. 

1. A DEVICE FOR ILLUSTRATING THE LEACHING ACTION OF A LIQUID AS ITMOVES INTO AND THROUGH SAID DEVICE FROM AN OUTER ENVIRONMENT COMPRISING A SUBSTANTIALLY TRANSPARENT TOP MEMBER HAVING A FLAT UPPER AND LOWER SURFACE AND A PREDETERMINED PERIPHERY; A SUBSTANTIALLY TRANSPARENT BOTTOM MEMBER ENGAGEABLE WITH AN ENGAGING SAID TOP MEMBER, HAVING A FLAT UPPER AND LOWER SURFACE AND A PERIPHERY EQUAL TO THAT OF SAID TOP MEMBER, ,SAID TOP AND BOTTOM MEMBERS EACH HAVING A PREDETERMINED THICKNESS; DISENGAGEABLE ENGAGING MEANS POSITIONED ON THE LOWER SURFACE OF THE TOP MEMBER AND ON THE UPPER SURFACE OF THE BOTTOM MEMBER ARRANGED IN JUXTAPOSITION WITH THE ENGAGING MEANS ON SAID TOP MEMBER WHEREBY SAID MEMBERS MAY BE ABUTTED IN SEPARABLE RELATIONSHIP; THE BOTTOM MEMBER HAVING INTERCONNECTING CANALS DISPOSED WITHIN ITS UPPER SURFACE WITH TERMINAL ENDINGS ALONG THE PERIPHERY OF SAID MEMBER SUCH THAT THE CANALS ARE COMPLETELY ENCLOSED WHEN THE TOP AND BOTTOM MEMBERS ARE IN AN ENGAGED POSITION, EXPOSED TO THE OUTER ENVIRONMENT ONLY AT SAID TERMINAL ENDINGS; AND AN AMOUNT OF INDICATOR MATERIAL DISPOSED WITHIN SAID CANALS WHICH UPON CONTACT WITH A SUITABLE LIQUID IS LEACHED OUT FROM THE CANALS INTO THE LIQUID IN THE OUTER ENVIRONMENT AS THE LIQUID FLOWS THROUGH THE CANALS. 